R version 4.6.0 alpha (2026-03-31 r89747 ucrt)
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Platform: x86_64-w64-mingw32/x64

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> # These functions perform several internal 
> # tests and call `stop()` on invalid states. 
> x <- hdf5lib::c_flags()
> y <- hdf5lib::ld_flags()
> 
> # Expect a string. Not NA or "".
> 
> if (!inherits(x, "character")) stop("x is not a character")
> if (!inherits(y, "character")) stop("y is not a character")
> 
> if (length(x) != 1) stop("x length is not 1")
> if (length(y) != 1) stop("y length is not 1")
> 
> if (is.na(x)) stop("x is NA")
> if (is.na(y)) stop("y is NA")
> 
> if (!nzchar(x)) stop("x is an empty string")
> if (!nzchar(y)) stop("y is an empty string")
> 
> proc.time()
   user  system elapsed 
   0.21    0.04    0.21